People with one or more tickets to an event (e.g., a sporting match) may have unused tickets available. This may present an opportunity for buyers, especially late buyers, who want tickets.
Online ticket markets are available (e.g., Stubhub™), but these require the ticket holder to be knowledgeable about price trends, and to invest time-intensive monitoring to secure an optimal price. Online services usually involve account setup and manual data entry related to the potential transaction/tickets.
Tickets have perishable value and the above constraints lead to situations where tickets go unsold and unused. Ticket owners lose sales, and event venues lose ancillary revenues (e.g., concessions).